Argon Debye temperature

The van der Waals attraction between gas molecules may originate from three possible sources permanent dipole-permanent dipole (Keesom) forces permanent dipole-induced dipole (Debye) interactions and transitory dipole-transitory dipole (London) forces. This, of course, ignores the higher multipole interactions. Only the classical London dispersion forces contribute to the long-range attraction between colloidal particles. These London interactions are the self-same forces that are responsible for the liquefaction of the rare gases, such as helium and argon, at low temperatures. 

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